Simple cuff electrodes, because they are easily fabricated, easily implanted, and highly reliable, have been the workhorse electrodes for most of the clinically applied neural prostheses in spite of their "off- on" characteristics. While electrodes that permit graduated neural activation would yield better control, they cannot now be fabricated in the form of a safe and practical cuff. This limitation has recently been overcome by investigators at Case Western Reserve University (CWRU), who have demonstrated selective activation of nerves in animals with a self- wrapping spiral cuff electrode of patented design. The CWRU electrodes are now fabricated one-at-a-time in a laborious, time consuming series of manual operations whose output is small and whose product in unreliable; to fully realize the benefits of CWRU's innovation, an improved, mass-producible versions must be developed. Such an electrode is the subject of Spire's proposal. Ion beam assisted deposition (IBAD) will be used to place a thin, highly adherent, conducting film on silicone rubber and standard semiconductor processing techniques (photolithography) used to define electrodes in it. This approach will allow reliable, repeatable production of the spiral cuff electrode design and make possible designs with smaller features and more stimulating surfaces. Prototype cuffs will be manufactured in Phase I. In Phase II, we will further refine the fabrication process and test the electrodes in extensive, long-term animal studies.